Classifications

• • C—CHEMISTRY; METALLURGY
  • C06—EXPLOSIVES; MATCHES
  • C06B—EXPLOSIVES OR THERMIC COMPOSITIONS; MANUFACTURE THEREOF; USE OF SINGLE SUBSTANCES AS EXPLOSIVES
  • C06B45/00—Compositions or products which are defined by structure or arrangement of component of product

Definitions

• the present invention relates to a novel malleable solid explosive, which constitutes an alternative, or even an improvement, to the plastic explosives known to date (see below).
• the invention also relates to a process for obtaining said novel malleable solid explosive.
• the technical field of the invention is that of malleable (pasty) solid (blocks of) explosives, commonly known as plastic explosives, primed with a detonator, for military and civil use. They are generally used in the form of cakes of a few hundred grams. The malleability of these explosive cakes makes it possible to fully adapt their forms to the contours of the objects or structures to be destroyed.
• Plastic explosives composed of an explosive charge and a binder such as wax or mineral oil, which have the drawback of having degraded malleability properties under cold conditions, have also being described in the past Patent application DE 20 27 209 described, in 1971, a malleable explosive containing, in order to improve its cold plasticity, from 8% to 15% by weight of silicone oil as binder (said explosive also advantageously contains zinc oxystearate as additive).
• a malleable explosive containing in order to improve its cold plasticity, from 8% to 15% by weight of silicone oil as binder (said explosive also advantageously contains zinc oxystearate as additive).
• patent application DE 30 46 562 proposes explosives of this type incorporated into metal or plastic sheets.
• plastic explosives contain an explosive charge (hexogen (RDX) and/or pentrite, for example), a rubber polymeric binder (which is most often synthetic such as a butadiene-styrene rubber or a polyisobutylene), a plasticizer (such as bis(2-ethylhexyl) adipate or sebacate, di-n-octyl phthalate or tri-n-butyl citrate), and additives (such as dyes, antioxidants and detection markers).
• RDX hexogen
• pentrite e.g., a rubber polymeric binder
• plasticizer such as bis(2-ethylhexyl) adipate or sebacate, di-n-octyl phthalate or tri-n-butyl citrate
• additives such as dyes, antioxidants and detection markers.
• the plasticizer (generally present in weight contents of from 2 to 5%) has the role of giving the plastic explosives their malleability and better mechanical strength not necessitating their conditioning in a structure (see the teaching of the prior art recalled above, relating to plasticizer-free malleable explosives).
• the most well known plastic explosives having this type of formulation are C-4 plastic and Semtex®, which are familiar to those skilled in the art. These plastic explosives thus contain, in their composition, with reference to their plastic nature, a rubber polymeric binder (solid) combined with a plasticizer. These two inert components do not participate in the desired explosive effect.
• the controlled dosing of the binder (polymer) and of the plasticizer which are generally introduced in small amounts (a few percent) into the energetic charge of the plastic explosive, complicates the process for manufacturing the plastic explosive.
• the inventor has sought a novel type of “plastic” explosive, more precisely a novel malleable solid explosive, which is more advantageous in terms of composition (free of plasticizer), performance (with a “less dilute” energetic charge) and manufacturing process (easier).
• a pasty component A comprising the explosive charge (and optionally other pulverulent ingredients such as aluminum) and a crosslinkable liquid polymer, such as hydroxytelechelic polybutadiene; and
• liquid component B comprising the agent for crosslinking said crosslinkable liquid polymer
• Said pasty component A obtained by simple mixing of its constituents in a blender
• Said pasty component A does not exist in the form of blocks, and is never molded. It is formulated only for the purpose of mixing it with the crosslinking agent and of subsequently crosslinking it, leading to the composite solid explosive.
• the present invention thus relates to a novel malleable solid explosive, which constitutes an alternative, or even an improvement, to the plastic explosives known to date (see above).
• Said explosive is solid inasmuch as it does not flow by gravity (at room temperature and above: in fact, up to the temperature at which the explosive charge it contains is no longer stable).
• Said explosive is malleable in the sense that it can be modeled by hand (manually) at temperatures of from ⁇ 40° C. to +70° C.
• the malleable solid explosive of the invention is characterized in that it is in the form of a block (solid) consisting, for at least 98% of its weight, of a pulverulent explosive charge and of a liquid chosen from polyol polymers of the group of polyisobutylene polyols, polybutadiene polyols, polyether polyols, polyester polyols and polysiloxane polyols, whose number-average molecular mass is between 500 and 10 000, and mixtures thereof.
• said malleable solid explosive of the invention combines physical presentation (state) and composition characteristics.
• the malleable solid explosive of the invention is thus in the form of a block, i.e. in the form of a compact mass. It is in fact a block, obtained by molding or by cutting a paste (see the process for obtaining it described below).
• the malleable solid explosive of the invention may thus be obtained by molding a pasty component A according to patent application EP-A-1 333 015.
• the invention currently claimed offers a novel outlet for this component A, proposes an entirely novel use thereof (in the context of the invention, said component is not crosslinked but used “in its native form” after a simple forming operation). It is noted, however, that the field of the invention is not in any way limited to said components A according to patent application EP-A-1 333 015.
• the pulverulent explosive charge (whose particle size(s), which are not novel per se, are conventionally generally between 2 and 500 ⁇ m) of the block contains one or more explosives (as a mixture). Said explosive(s) present advantageously have different particle sizes (granulometric fractions). It is thus possible to have high charge contents.
• the pulverulent explosive charge of the block represents at least 85% by weight relative to the total weight of the block.
• the liquid present also consists of a liquid (chosen from the polyol polymers mentioned above) or a mixture of liquids (chosen from the polyol polymers mentioned above). It may or may not be a solvent of the pulverulent explosive charge. In the case where said liquid is a solvent for said charge, it is understood that said charge is present in concentrations above the saturation concentration, insofar as a solid block is under consideration.
• the malleable solid explosive block consists essentially (for at least 98% of its weight) of said charge and said liquid. In addition to said charge and said liquid, it is liable to contain only additives (see below). It may quite entirely consist solely (100%) of said charge and said liquid. No plasticizer is present in its composition.
• the (S/L) weight ratio is in principle high. It has been seen above that the pulverulent explosive charge of the block advantageously represents at least 85% by weight relative to the total weight of the block. Moreover, a liquid with a dynamic viscosity of between 0.1 and 1 Pa ⁇ s in the temperature range: ⁇ 40° C. to +70° C. and an explosive charge with a particle size of between 1 and 150 ⁇ m are advantageously combined. Most advantageously, a solid explosive charge having several granulometric fractions between 1 and 150 ⁇ m is chosen.
• the explosive charge of the solid explosive blocks of the invention is not novel per se. It may consist especially of octogen (HMX), hexogen (RDX), pentaerythrityl tetranitrate (pentrite or PETN), hexanitrohexaazaisowurtzitane (CL20), triaminotrinitrobenzene (TATB), 5-nitro-2,2,4-triazol-3-one (ONTA), hexanitrostilbene (HNS), 1,1-diamino-2,2-dinitroethane (DADNE or Fox-7) or a mixture thereof. It is advantageously chosen from octogen, hexogen, pentrite and CL20. Hexogen is the preferred explosive (energetic) charge of the blocks of the invention.
• the liquid is thus chosen from the polyol polymers below: polyisobutylene polyols, polybutadiene polyols, polyether polyols, polyester polyols and polysiloxane polyols, with a number-average molecular mass of between 500 and 10 000, and mixtures thereof.
• Said liquid is advantageously chosen from said polybutadiene polyols and mixtures thereof.
• Said liquid most advantageously consists of a hydroxytelechelic polybutadiene of this type.
• the hydroxytelechelic polybutadienes usually used in crosslinked form as binder for solid propergols for self-propulsion are entirely suitable for use as liquid for the malleable solid explosives of the invention.
• this type of polymer see especially the teaching of patent application EP-A-1 333 015).
• said charge and said liquid constitute from 98% to 100% (by weight) of the malleable solid explosive of the invention, of the malleable solid explosive blocks of the invention.
• Said explosive blocks are in fact liable to contain additives, especially antioxidants, anti-age-curing agents, chemical detection markers, to not more than 2% of their total weight.
• Additives that may be contained in said explosive blocks are especially:
• At least one antioxidant for instance di-tert-butyl-para-cresolmethane, 2,2-methylenebis(4-methyl-6-tert-butyl)phenol, and mixtures thereof;
• At least one anti-age-curing agent especially for preventing hot curing, for instance a silicone oil, tetraethylenepentamineacrylonitrile (TEPAN), soybean lecithin, and mixtures thereof;
• a silicone oil for instance a silicone oil, tetraethylenepentamineacrylonitrile (TEPAN), soybean lecithin, and mixtures thereof;
• At least one chemical detection marker for instance EGDN (ethylene glycol dinitrate), DMDNB (2,3-dimethyl-2,3-dinitrobutane), p-MNT (para-mononitrotoluene) or o-MNT (ortho-mononitrotoluene).
• EGDN ethylene glycol dinitrate
• DMDNB 2,3-dimethyl-2,3-dinitrobutane
• p-MNT para-mononitrotoluene
• o-MNT ortho-mononitrotoluene
• the malleable solid explosive block of the invention contains, as weight percentages:
• a pulverulent explosive charge (a single charge or a mixture of charges of different nature and/or particle size)
• a polyol polymer liquid of the type mentioned above a single liquid or a mixture of at least two liquids.
• the blocks of the invention generally have a mass of between 100 g and 5 kg.
• Said malleable solid explosive blocks may be considered as cakes (in the sense of the plastic explosive cakes of the prior art).
• the blocks of the invention have rheological qualities and performance that are higher than those of the malleable explosive blocks incorporating a plasticizer. They can be stored and used as cakes of high mass (for example several kilograms) without any precaution with reference to their mechanical strength, unlike the plasticizer-free malleable explosives of the prior art.
• the present invention relates to a process for obtaining a malleable solid explosive as described above (first subject of said invention). Said process comprises:
• the blending of pulverulent explosive charge+polyol polymer liquid, to obtain the paste may be performed at room temperature or at elevated temperature.
• the blending temperature is obviously compatible with the safety standards, with regard to the exact nature of the explosive charge. In this spirit, it is generally less than 80° C.
• the process for obtaining the novel explosive of the invention may be performed in continuous or batch mode.
• the constituents of the blocks of the invention are mixed together at elevated temperature (typically 60° C.) in a blender; the mixture obtained (the mass of which may range, for example, from 100 kg to 5 tons) is then discharged in the blender and introduced into a funnel terminated with an endless screw; said mixture is entrained by the endless screw so as to be deposited in molds (whose volume may be variable, typically between 100 and 700 cm 3 depending on the targeted applications, generally 350 cm 3 ); said mixture contained in each molds is then removed from the molds to obtain a malleable explosive block.
• elevated temperature typically 60° C.
• the mixture obtained the mass of which may range, for example, from 100 kg to 5 tons
• a funnel terminated with an endless screw said mixture is entrained by the endless screw so as to be deposited in molds (whose volume may be variable, typically between 100 and 700 cm 3 depending on the targeted applications, generally 350 cm 3 ); said mixture contained in each molds is then removed from the molds to obtain a malleable explosive block.
• the mixture is obtained by continuous hot blending and then directly extruded in molds (whose volume may be variable, typically between 100 and 700 cm 3 according to the targeted applications, generally 350 cm 3 ).
• the mixture is obtained by continuous hot blending and is then extruded directly, the extruded rod being chopped so as to obtain blocks of determined mass directly.
• the mass per unit volume (density) of the explosive block obtained may vary as a function of the amount of air trapped in the explosive charge during the production process. Said mass per unit volume (density) is advantageously between 1300 and 1700 kg/m 3 .
• Table 1 below shows the composition of said malleable solid explosive according to the invention.
• the liquid is a hydroxytelechelic polybutadiene (HTPB). It is the HTPB R45HTLO sold by the company Sartomer (Mn ⁇ 3000). It is incorporated to about 10% by weight.
• HTPB hydroxytelechelic polybutadiene
• the pulverulent explosive charge (which is incorporated to 88% by weight) consists of RDX. It more specifically consists of two RDX charges of different particle size, referenced as charge 1 and charge 2 in Table 1.
• the particle size of these two charges 1 and 2 is given by three values read on the cumulative curve of the volume percentage of particles as a function of the diameter (equivalent spherical diameter) of the particles, which is cumulative according to increasing diameters:
• D 50 diameter for which the cumulative volume percentage is equal to 50%
• D 90 diameter for which the cumulative volume percentage is equal to 90%.
• the weight composition of the malleable solid explosive block moreover contains additives (an antioxidant, an anti-age-curing agent and a chemical marker), to less than 2% of its total weight.
• the constituents of the malleable solid explosive block of the invention are blended at elevated temperature (60° C. +/ ⁇ 10° C.), each blending operation using about 200 kg of material.
• the paste obtained is then emptied out and introduced into a funnel equipped with an endless screw in order to fill the molds.
• the volume of the molds is about 50 cm 3 .
• the malleable explosive solid block generated in each mold is then stripped from the mold to obtain a malleable explosive cake of about 0.5 kg.
• the mass per unit volume (density) of the explosive cakes obtained via this process may vary as a function of the amount of air trapped in the paste during the process. Said mass per unit volume (density) is between 1480 and 1520 kg/m 3 .

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• Chemical & Material Sciences (AREA)
• Crystallography & Structural Chemistry (AREA)
• Organic Chemistry (AREA)
• Processes Of Treating Macromolecular Substances (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
• Other Resins Obtained By Reactions Not Involving Carbon-To-Carbon Unsaturated Bonds (AREA)

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• 2009
  • 2009-12-21 FR FR0959290A patent/FR2954309B1/fr not_active Expired - Fee Related
• 2010
  • 2010-12-20 WO PCT/FR2010/052827 patent/WO2011083249A1/fr active Application Filing
  • 2010-12-20 AU AU2010340832A patent/AU2010340832B2/en not_active Ceased
  • 2010-12-20 US US13/515,367 patent/US20120305148A1/en not_active Abandoned
  • 2010-12-20 JP JP2012545381A patent/JP2013514962A/ja active Pending
  • 2010-12-20 EP EP10810850.7A patent/EP2516356B1/fr active Active
  • 2010-12-20 BR BR112012015076A patent/BR112012015076A2/pt not_active IP Right Cessation
  • 2010-12-20 CA CA2784311A patent/CA2784311C/fr not_active Expired - Fee Related
  • 2010-12-20 ES ES10810850T patent/ES2796830T3/es active Active
  • 2010-12-20 RU RU2012129733/05A patent/RU2541079C2/ru not_active IP Right Cessation
  • 2010-12-20 SG SG2012045522A patent/SG181832A1/en unknown
  • 2010-12-20 KR KR1020127019249A patent/KR20120108014A/ko not_active Application Discontinuation
  • 2010-12-20 CN CN201080058611.1A patent/CN102666438B/zh not_active Expired - Fee Related
• 2012
  • 2012-06-14 IL IL220431A patent/IL220431A/en not_active IP Right Cessation

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